Issues with division by scalar of boost::units::quantity

Hello,

I have stumbled upon another issue in combination with boost.units. The DVecScalarDivExpr implements the division by scalar in the following way:

return ReturnType( ~vec, ScalarType(1)/ScalarType(scalar) );

However, the problem I am having is that boost.units prevents the direct cast from basic data types to a boost::units::quantity. The library requires a quantity to be passed to the constructor, such as boost::units::si::metre. I am not sure how I would resolve this while staying agnostic with respect to the data types being used, but for now I can make it work by inverting the scalar and then multiplying by the result.

Code with error message:

const boost::units::quantity<boost::units::si::length, double> bandwidth = 1.0 * boost::units::si::metre;
const blaze::StaticVector<boost::units::quantity<boost::units::si::length, double>, 2, blaze::columnVector>
                sample = {1.0 * boost::units::si::metre, 1.0 * boost::units::si::metre};
const double weights = blaze::norm(sample / bandwidth);

“Fixed” code:

const auto bandwidthInv = 1.0 / boost::units::si::metre;
const blaze::StaticVector<boost::units::quantity<boost::units::si::length, double>, 2, blaze::columnVector>
                sample = {1.0 * boost::units::si::metre, 1.0 * boost::units::si::metre};
const double weights = blaze::norm(sample * bandwidthInv);

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Error log:

/usr/local/include/blaze/math/expressions/DVecScalarDivExpr.h:1085:32: error: no matching conversion for functional-style cast from 'int' to 'ScalarType' (aka 'boost::units::quantity<boost::units::unit<boost::units::list<boost::units::dim<boost::units::length_base_dimension, boost::units::static_rational<-1, 1> >, boost::units::dimensionless_type>, boost::units::homogeneous_system<boost::units::list<boost::units::si::meter_base_unit, boost::units::list<boost::units::scaled_base_unit<boost::units::cgs::gram_base_unit, boost::units::scale<10, static_rational<3> > >, boost::units::list<boost::units::si::second_base_unit, boost::units::list<boost::units::si::ampere_base_unit, boost::units::list<boost::units::si::kelvin_base_unit, boost::units::list<boost::units::si::mole_base_unit, boost::units::list<boost::units::si::candela_base_unit, boost::units::list<boost::units::angle::radian_base_unit, boost::units::list<boost::units::angle::steradian_base_unit, boost::units::dimensionless_type> > > > > > > > > >, void>, double>')
      return ReturnType( ~vec, ScalarType(1)/ScalarType(scalar) );
                               ^~~~~~~~~~~~
/Users/dwright/projects/dv-laser-calibration/maths/MeanShift.hpp:133:46: note: in instantiation of function template specialization 'blaze::operator/<blaze::StaticVector<boost::units::quantity<boost::units::unit<boost::units::list<boost::units::dim<boost::units::length_base_dimension, boost::units::static_rational<1, 1> >, boost::units::dimensionless_type>, boost::units::homogeneous_system<boost::units::list<boost::units::si::meter_base_unit, boost::units::list<boost::units::scaled_base_unit<boost::units::cgs::gram_base_unit, boost::units::scale<10, static_rational<3> > >, boost::units::list<boost::units::si::second_base_unit, boost::units::list<boost::units::si::ampere_base_unit, boost::units::list<boost::units::si::kelvin_base_unit, boost::units::list<boost::units::si::mole_base_unit, boost::units::list<boost::units::si::candela_base_unit, boost::units::list<boost::units::angle::radian_base_unit, boost::units::list<boost::units::angle::steradian_base_unit, boost::units::dimensionless_type> > > > > > > > > >, void>, double>, 2, false, blaze::aligned, blaze::padded, blaze::GroupTag<0> >, boost::units::quantity<boost::units::unit<boost::units::list<boost::units::dim<boost::units::length_base_dimension, boost::units::static_rational<1, 1> >, boost::units::dimensionless_type>, boost::units::homogeneous_system<boost::units::list<boost::units::si::meter_base_unit, boost::units::list<boost::units::scaled_base_unit<boost::units::cgs::gram_base_unit, boost::units::scale<10, static_rational<3> > >, boost::units::list<boost::units::si::second_base_unit, boost::units::list<boost::units::si::ampere_base_unit, boost::units::list<boost::units::si::kelvin_base_unit, boost::units::list<boost::units::si::mole_base_unit, boost::units::list<boost::units::si::candela_base_unit, boost::units::list<boost::units::angle::radian_base_unit, boost::units::list<boost::units::angle::steradian_base_unit, boost::units::dimensionless_type> > > > > > > > > >, void>, double>, false, nullptr>' requested here
                        const double weights = blaze::norm(sample / bandwidth);
                                                                  ^

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